1. Field of the Invention
The present invention relates to a device for applying a liquid to pasty medium to a moving surface, the moving surface in the case of direct application being the surface of a paper, board or other fibrous web. In the case of indirect application the moving surface being the surface of a transfer element, for example an applicator roll, which transfers the application medium to the surface of the fibrous web, an applicator for applying the medium and a doctor device arranged downstream in the running direction of the moving surface for doctoring off and/or equalizing the medium applied to the moving surface.
2. Description of the Related Art
Application devices are known, where during application of the medium with the applicator, for example in the case of a nozzle applicator, where the liquid to pasty medium is applied under pressure to the surface to be coated, not all parts of the medium reach the moving surface and therefore spray into the surroundings. The collection of the spray is carried out with what is known as a discharge tray, which is normally fixed directly to the applicator and ends underneath a discharge plate belonging to the doctor device and overlapping the latter slightly. However, this construction has various disadvantages.
Firstly, the medium running off the discharge plate of the doctor device or wiped off by a doctor element, such as a blade, doctor bar, or a rotating metering rod, such as coating, size, starch, impregnant, splashes forcibly in free fall onto the discharge tray located underneath, which also collects the medium originating from the application device. As a result, high spraying movements are produced of a type which both reach machine parts and, as a result, ensure defects, and reach the freshly coated surface again and there have a negative influence on the application result.
In addition, on account of the rigid design of the discharge plate and the discharge tray which, in the operating state, are located with their free ends close to each other, limits are placed on the freedom of movement during pivoting-away movements of the applicator and the doctor device.
What is needed in the art is a device for collecting the excess medium which minimizes or eliminates splashing of the medium, and which is not rigid.